#' @name mact_table
#' @docType data
#' @title mact_table (DATA) MACT NESHAP subparts (the code and the description)
#' @description 
#'    This is a data.table with one row per MACT subpart such as BBBBBB or ZZZZZZ 
#'    and the title of each category. From the ECHO download of ICIS Air
#'  @seealso [frs_by_mact] 
NULL
